A team of Australian scientists led by Dr. Marti Kramski at the University of Melbourne injected pregnant cows with the HIV protein and discovered that they produced milk after birth that was loaded with HIV antibodies. In other words, the cows were effectively immunized against the disease.

Researchers then harvested the antibodies and discovered that they can prevent the virus from infecting humans. "We were able to harvest antibodies specific to the HIV surface protein from the milk," said Kramski. "We have tested these antibodies and found in our laboratory experiments that they bind to HIV and that this inhibits the virus from infecting and entering human cells."

So what's the next step? The cow-milk antibodies will be developed into a cream that women can use to prevent transmission of the virus during sex. This will, Kramski hopes, "empower women" to protect themselves: "We hope that our anti-HIV milk antibodies will provide a user-friendly, female-controlled, safe and effective tool for the prevention of sexually acquired HIV infection."